Findings from the federally funded evaluation of the Centers for Medicare & Medicaid Services’ State Innovation Models (SIM) initiative are presented in this report, which focuses on the experiences of the 11 states awarded Model Test funding during round 2 of SIM: Colorado, Connecticut, Delaware, Idaho, Iowa, Michigan, New York, Ohio, Rhode Island, Tennessee, and Washington. Using $622 million in federal funds over four years (2015–18), these states engaged a broad range of stakeholders and used various policy levers to encourage the spread of innovative health care models—often building on prior efforts to improve health outcomes. This report describes states’ early experiences implementing their efforts, from February 2015 to June 2016.